This invention relates to polyamide and olefin/vinyl alcohol copolymer blends.
Olefin/vinyl alcohol copolymers which have a high resistance to oxygen permeability and the low water vapor transmission rate are disclosed in U.S. Pat. No. 3,585,177.
Laminates containing ethylene vinyl alcohol copolymer layers are known in the art. Layers of ethylene vinyl alcohol copolymer have been laminated adjacent to various polyolefin materials, modified polyolefin materials, polyamides, ethylene vinyl acetate copolymer, ethylene acrylic acid copolymer, and ionomers. The various laminates are designed to take advantage of the unique properties of the specific polymers contained in each laminate structure.
Of particular interest are U.S. Pat. Nos. 4,254,169, 3,595,740 and 3,949,114, all showing ethylene vinyl alcohol copolymer layers and laminates in which there is one layer of a polyamide, usually polycaprolactam, adjacent to one side of the ethylene vinyl alcohol copolymer layer.
U.S. Pat. No. 3,882,259 shows the use of ethylene vinyl alcohol copolymers blended with ethylene vinyl acetate copolymer or an ionomer. The ethylene vinyl acetate or ionomer will cause a reduction in oxygen barrier properties and generally an increase in adhesion to adjacent layers.
U.S. Pat. No. 3,636,136 disclosed compositions of polyamides having melt temperatures below 170.degree. C. and ethylene/vinyl alcohol copolymers containing greater than 70 mole percent ethylene for use as textile fusible adhesives used in the preparation of color concentrates.